A stator described in Japanese Laid-Open Patent Publication No. 2009-38918 includes an armature core formed by laminating a plurality of core sheets on one another. A plurality of teeth extending in a radial direction of the armature core, and a plurality of slots are formed in the armature core. Sheet-like insulating members are inserted into the slots, and conductors are inserted into the insulating members. The insulating members located between the armature core and the conductors ensure insulation properties between the armature core and the conductors. It is known that if the stator is provided with SC coils, i.e., segment conductor coils, the space factor of the coils is increased.
In the stator described in Patent Document 1, ends of each tooth in an axial direction thereof are provided with soft portions. According to this configuration, when the conductor inserted into the slot is bent in the circumferential direction, it is possible to prevent the insulating member located between the armature core and the conductor from being damaged by a corner portion of an axial opening of the slot.
However, if the ends of the teeth in the axial direction are provided with such soft portions, additional soft portions must be provided separately from existing parts that configure the stator, such as the armature core, the conductors, and the insulating members. This increases the manufacturing costs. Further, to more effectively prevent the insulating member from being damaged by the soft portions, it is desirable that the soft portions be made to project inward of the slots to prevent the insulating members from coming into contact with the corner portions. In this case, however, the space factor of the coils is lowered.
The present invention has been accomplished in view of such circumstances, and it is an objective of the invention to provide a method for manufacturing a stator, a stator and a motor configured to ensure insulation properties with respect to conductors, and an armature core, while preventing the manufacturing costs from increasing and preventing the space factor from lowering.